Attachment for steel squares and the like.



j. H. JOHNSON.

ATTACHMENT FOR SEEL SQUARES AND THE LIKE.

FPUCATION FILED MAY 2. |916` Patented May 8, 1917.

NEl

me/Wto@ JOHN H. JOHN-SON, OF OMAHA, NEBRASKA.

ATTACHMENT FOR STEEL SQUARES AND THE LIKE.

Application led May 2, 1916.

To ZZ fic/tom t 'may concern Be it known that l, loi N H. flouissrnv, a citizen ot the lUnited States, residing at (lmaha, in the county ot Douglas and State of Nebraska, have invented a new and useiul Attachment 'for Steel Squares and the like, and have described the same in the iollowing specification, illustrated by the accompanying drawings.

My invention relates to that class ot adjustable and removable attachments ivhich are commonly applied to steel squares, and span the interior angles ot steel squares, used by carpenters in building and remodeling operations, lor laying out their work, and 'tor determining and transferring to and from the raiters, braces and other material parts and elements et buildings and other structures, the requisite or desired lines, bevels, pitches, angles, cuts, joints, measurements and correlative positions. It is the object of the invention to point out in terms ot' rise and run on the arms ot the common steel square the grade, or pitch, of any existing inclined edge, surface or line to Which the square may be applied; by means oi such a square, supplied With this attachment, to set at any required angle with a given line any straight piece of building material to which the square is applied; to obviate all need of having a spirit level, or its equivalent, permanently incorporated in the square, or in either of its arms; to render the device attac-hable to the inner edges of the arms of the square, While the outer edges oi' the same remain free for unobstructed contact With the Work or structure to Which the square is applied; to render the attachment operatively applicable to the square, and attachable thereto, Without drilling or otherwise perforating the square itself, or either et' its arms; at the same time to adapt the attachment, when separated from the square, and fastened to a straight-edge, to produce in combination with the straight-edge a complete and convenient carpenters level; and in general to increase the usefulness of the typical steel square. To accomplish this object, l incorporate in my improved attachment, as parts thereof', a bar having longitudinally alined sections Which are united by a sliding joint, a spirit level which is carried by one of the sections, and junction members, .Which are carried by the sections respectively, and are adapted to engage the arms of the square.

Specification of Letters Patent.

Patented May 8, 1917.

Serial No. 94,976.

In the accompanying drawings, illustrating the best manner in vvhich l have contemplated applying the principles of the invention, Figure 1 is a side elevation ot an attachment of the specified class, which is constructed in accerdance with these principles and operatively applied to a steel square. Fig. 2 is a side elevation ot the same attachment, diiterently adjusted and operatively applied to one arm of the square. Fig. 3 is longitudinal central section of the same attachment dillerently adjusted. Fig. a is a cross section of the same on the section line -l--lf in Fig. the device and its associated steel square, operatively applied to a root rafter for the purpose of determining its pitch.

ln these drawings the numerals 12 and 13 denote respectively the blade and the tongue ot a typical rectangular steel square, having, marginally marked thereon, the usual graduated scales indicated by the numerals l to 1l inclusive. The illustrated specimen of my invention, variously applied to this square, comprises the axially alined tubular sect-ions l-l and 15, and is variable in length by the telescoping of these sections. Each section, being open at its telescoping end, is closed at its opposite end by deformatively pressing its opposite semicircular peripheral walls together and thereby forining a. fiat terminal ear 16, curvilinear in outline, Wider from side to side than the body of the tube, and co-axial therewith. A pair of guides 17, spaced apart by the ear, and having the index fingers 1S extending beyond its margin in parallel planes, are adjustably pivoted thereto on the screw bolt 19, which passes centrally through the ear and is provided v-:ith the thumbnut 20. The outer tube 14: carries the spirit level 21 and has an air-hole 22.

Operatively to adapt either arm of the square to be used as a level, aiix the attachment thereto, in parallelism therewith as in Fig. 2, by placing the ears 16 in edgeWise contact with the arm, turn the index lingers to vertical overlapping positions on the opposite sides of the arm, and clamp them thereto by turning the thumbnuts. To convert a straight edge into a level, aflix the described attachment thereto in the same manner. To determine operatively the pitch of a given line, as for example the pitch of the ratter 23, place one arm of the square along the rafter, as in Fig. 5,

Fig. 5 is a side elevation of aliix the attachment in a horizontal position, subtending the angle of the square, by placing the ears 16 in edgewise contact with the arms of the square respectively, as shown, and by turning the pairs of fingers 1S pivotally to alined positions overlapping the arms of' the square. rl`he rise and run of the rafter may t-hen be read at the points otl intersection of the fingers with the arms i3 and l2 respectively. Thus the pitch read on Fig. l is rise three and three-quarters, and run five and one-half; which may be taken as inches, feet, or other units of long 1 easure. ln this way the square and the attachment together can be used as a slide rule on which the rise of the inclined surface or line can be read, when the run is given; and the run, when the rise is given` I claim as my inventionl. An attachment for steel squares and the like, comprising a bar having tivo alined sections united by a telescoping engagement; a spirit level mounted on one of the sections; and terminal junction members, pivotedl to the ends of the bar respectively, and adapted to engage the limbs of the square.

2. An attachment of the specified class, comprising two telescoping tubes; a level mounted on one of the tubes in parallelism therewith; and junction members carried by the tubes respectively for engagement With a steel square or the like.

3. An attachment of the specified class, comprising` tivo alined sections united by a telescopinov engagement; a level carried by one of the sections; and terminal junction members pivoted to the sections respectively.

l. An attachment of the specified class, comprising a bar of variable length; a spirit level carried thereby; and terminal junction members pivoted to the bar and having index fingers.

5. An attachment of the specified class, comprising a bar having a level carried thereby; and terminal clamps pivoted to the bar and provided with index fingers.

6. An attachment of the specified class, comprising a bar having a level carried thereby; index fingers pivotally mounted on the ends of the bar, and means for clamping the fingers in different positions of pivotal adjustment.

JOHN H. JOHNSON.

Copies of this patent may be obtained for ve cents each, by addressing the Commissioner of Patents Washington, 2D. C. 

